pciback: Avoid large array allocation on kernel stack.

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>

diff --git a/drivers/xen/pciback/conf_space_capability_msi.c b/drivers/xen/pciback/conf_space_capability_msi.c
index 1336be2a2af76f29fe43345c2bd40408f8f03a8a..2d7615f4b6e4fd5a834f89f45f627922486da227 100644 (file)
--- a/drivers/xen/pciback/conf_space_capability_msi.c
+++ b/drivers/xen/pciback/conf_space_capability_msi.c
@@ -2,6 +2,7 @@
  * PCI Backend -- Configuration overlay for MSI capability
  */
 #include <linux/pci.h>
+#include <linux/slab.h>
 #include "conf_space.h"
 #include "conf_space_capability.h"
 #include <xen/interface/io/pciif.h>
@@ -37,13 +38,16 @@ int pciback_disable_msi(struct pciback_device *pdev,
 int pciback_enable_msix(struct pciback_device *pdev,
                struct pci_dev *dev, struct xen_pci_op *op)
 {
-       int i;
-       int result;
-       struct msix_entry entries[op->value];
+       int i, result;
+       struct msix_entry *entries;
 
        if (op->value > SH_INFO_MAX_VEC)
                return -EINVAL;
 
+       entries = kmalloc(op->value * sizeof(*entries));
+       if (entries == NULL)
+               return -ENOMEM;
+
        for (i = 0; i < op->value; i++) {
                entries[i].entry = op->msix_entries[i].entry;
                entries[i].vector = op->msix_entries[i].vector;
@@ -56,6 +60,8 @@ int pciback_enable_msix(struct pciback_device *pdev,
                op->msix_entries[i].vector = entries[i].vector;
        }
 
+       kfree(entries);
+
        op->value = result;
 
        return result;